The proposed research is an extension of an ongoing project concerning the development of object perception and recognition in human infants. The focus has narrowed to a study of two object characteristics, structure and texture, both of which are three-dimensional. The goal is to identify and describe the processes underlying recognition of objects and object characteristics and, in particular, to study processes which are unique to objects' three-dimensional properties. In all cases, recognition refers to the ability to recognize an object in a new context or orientation or from a different perspective. In order to meet the general goal, five specific areas of investigation have been proposed. First, to understand better how infants learn to recognize structure, the effect of symmetry and distinctness of detail on speed of learning will be studied. Second, for theoretical reasons, object movement should facilitate recognition of an object's spatial characteristics; therefore, the effect of movement on recognition of an object's size and structure wll be studied in 2- to 6-month-old infants. Third, the investigation of the role of touch in recognition of structure and texture will be continued from the current project in a more complicated design intended to clarify several important but difficult questions. Fourth, there will be an attempt to correlate infant's spontaneous exploration of objects with their ability to learn about particular object characteristics. Patterns of eye movements during visual exploration will be studied in infants younger than 5 months and visual-haptic exploration will be studied in older infants. Finally, low-birth-weight infants will be compared to normal infants on tracking of and learning from moving objects and on the ability to recognize the texture and structure of a group of objects. Several different methods will be employed in the investigation and it is hoped that the study of recognition of structure and texture from several different angles will make it possible to understand the complex processes underlying the development of object recognition.